Comparison of Long-Acting Injectable Antipsychotics With Oral Antipsychotics and Suicide and All-Cause Mortality in Patients With Newly Diagnosed Schizophrenia

Abstract

Schizophrenia is generally considered to be among the most severe psychiatric disorders because of the excessive mortality associated with it. Research to find means to reduce this excessive mortality is warranted. To investigate associations of long-acting injectable antipsychotics (LAIs) with all-cause, natural-cause, and suicide mortality risks as well as the impacts of early use of LAIs in patients with newly diagnosed schizophrenia. This cohort study used data from the Taiwan National Health Insurance Research Database to construct a population-based cohort of patients with schizophrenia who received oral antipsychotics (OAPs) from January 1, 2002, to December 31, 2017. Within this cohort, the LAI group was defined as patients who switched to LAIs and were prescribed LAIs at least 4 times within 1 year. The LAI group was propensity matched 1:1 to patients who continued receiving OAPs of the same compounds. All patients were followed up until switching the antipsychotic administration route, death, or the end of the study (December 31, 2018), whichever occurred first. Data analysis was performed from January 2002 to December 2018. All-cause mortality, natural-cause mortality, suicide mortality, and suicide attempts. In total, 2614 patients who switched to LAIs (median [interquartile range] {IQR} age, 30 [23-39] years) and 2614 who received OAPs (median [IQR] age, 30 [23-39] years) were included (1333 male patients [51.0%] in each group). During the 16-year follow-up period (median [IQR] follow-up of 14 [10-17] years), patients who switched to LAIs had lower risks of all-cause mortality (adjusted hazard ratio [aHR], 0.66; 95% CI, 0.54-0.81), natural-cause mortality (aHR, 0.63; 95% CI, 0.52-0.76), and suicide attempts (incidence rate ratio, 0.72; 95% CI, 0.55-0.93) compared with patients who received the corresponding OAPs. A 47% lower suicide mortality risk (aHR, 0.53; 95% CI, 0.30-0.92) was observed in patients who switched to LAIs within the first 2 years of OAP initiation. These findings suggest that LAI use in patients with newly diagnosed schizophrenia is associated with decreased all-cause mortality and suicide risk. Furthermore, early treatment with LAIs within the first 2 years of OAP initiation was associated with a decrease in suicide mortality risk. Thus, LAI use in the early stage of treatment should be actively considered for patients with newly diagnosed schizophrenia.